6a13/6a12 want to upgrade your turbo check this out
Its called the JPDC 3/S TD05 (aka 9b-14b) Adapter Plate Kit
This is from there page
The Supra, 300ZX and RX7 - what do these have the 3/S's don't??? Big stock turbos.Â* The 14B is about the right size to compete with the other cars stock turbos, and so we are out to make it possible. What the factory screwed up, we want to correct.Â* The 14B flows 405cfm @15psi (rated) this will require you to upgrade the wussy stock injectors, fuel pump, and thus Air Fuel control too- BUT, you'll finally feel what it should have been feeling from the word GO.Â* The 14B plates will allow you to use TD05-14B's off of stock DSM 1st Gen Manuals, TD05-16G's, and Big 16G's. They'll connect to the stock manifolds, and both stock and Stillen style downpipes.
As I see it owners of 6a12 would be able to use the 14b etc but persons with the 6a13 will have to find a turbo replacement but dont have to get a manifold made